EP2457519B1

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Publication number: EP2457519B1
Application number: EP12155827.4A
Authority: EP
Inventors: Paul A. Scirica
Original assignee: Covidien LP
Current assignee: Covidien LP
Priority date: 2007-08-31
Filing date: 2008-08-29
Publication date: 2017-12-13
Anticipated expiration: 2028-08-29
Also published as: AU2008207624A1; US9814461B2; JP2009101136A; CA2639177A1; EP2030579A2; US20080308605A1; JP5761869B2; US20210106325A1; EP2030579A3; US11350930B2; US9004340B2; US7866525B2; JP2013128791A; US8245900B2; US20200029961A1; US20150182219A1; ES2396594T3; US10542975B2; JP5333899B2; US20140332582A1

Description

BACKGROUND

Technical Field

The present disclosure relates to a surgical instrument and disposable loading unit including a plastic surface thereon. More particularly, the present disclosure relates to a surgical instrument which includes a plastic surface on at least one of a closure apparatus and a contact surface of a tool assembly.

Background

Surgical devices wherein tissue is first grasped or clamped between opposing jaw structure and then joined by surgical fasteners are well known in the art. In some instruments, a knife is provided to cut the tissue which has been joined by the fasteners. The fasteners are typically in the form of surgical staples but two part polymeric fasteners can also be utilized.
Instruments for this purpose may include two elongated members which are respectively used to capture or clamp tissue. Typically, one of the members carries a staple cartridge that houses a plurality of staples arranged in at least two lateral rows while the other member has an anvil that defines a surface for forming the staple legs as the staples are driven from the staple cartridge. In some instruments, the closure of the two elongated members, or tool assembly, is affected by actuation of a movable handle which moves a drive beam having a closure apparatus thereon into a contact surface of a tool assembly, thus approximating the members of the tool assembly. A large frictional force may be present between the closure apparatus and the contact surface of the tool assembly, thus possibly requiring a relatively large amount of force to be applied to the movable handle.
DocumentEP 1 702 568 A1 discloses a surgical stapler having a closure member.
DocumentUS 5,482,054 discloses a method of manufacturing a jaw of an endoscopic bipolar cautery biopsy forceps by providing holes in a skeleton portion and use insert-type injection molding technique.

SUMMARY

In accordance with the present invention, a method of providing an insert having a low coefficient of friction on a closure member of a surgical device is disclosed which includes the steps of providing a closure member being configured to engage the contact surface of a tool assembly of said surgical instrument, said closure member including an upper flange portion, a lower flange portion and a vertical beam portion, interconnecting the upper flange portion and
the lower flange portion, the upper and lower flange portions having an internal surface and an external surface; drilling a hole through at least one of the upper and lower flange portions, the hole extending from the external surface to the internal surface of the at least one upper and lower flange portion; and injecting a material having a low coefficient of friction through the hole using an injection molding process to
cover at least a portion of the internal surface of the at least one upper and lower flange portion. In one embodiment, the moldable material is plastic.
In one embodiment, the step of providing a hole includes the step of providing a hole through both the upper flange portion and the lower flange portion, and the step of injecting a moldable material includes the step of injecting a moldable material through each of the holes in the upper and lower flange portions.
In one embodiment, the internal surface of each of the upper and lower flange portions defines at least one recess and the moldable material is injected into the recesses through the holes.

DESCRIPTION OF THE DRAWINGS

Various embodiments of the presently disclosed surgical instrument are disclosed herein with reference to the drawings, wherein:

FIG. 1 is a side perspective view from the distal end of one embodiment of the presently disclosed surgical instrument with articulating tool assembly;
FIG. 1A is a side perspective view from the proximal end of a disposable loading unit (DLU) of the surgical instrument shown inFIG. 1 including the tool assembly;
FIG. 2 is a side perspective view of the distal end of mounting assembly and tool assembly, with parts separated, of the DLU of the surgical instrument shown inFIG. 1;
FIG. 3 is a side perspective view of the mounting assembly and the proximal body portion of the DLU shown inFIG. 1A with parts separated;
FIG. 3A is a side perspective view of a coupling member of the surgical instrument shown inFIG. 1;
FIG. 3B is a side perspective view of an upper mounting portion of the mounting assembly of the DLU of the surgical instrument shown inFIG. 1;
FIG. 3C is a side perspective view of a lower mounting portion of the mounting assembly of the DLU of the surgical instrument shown inFIG. 1;
FIG. 3D is a side perspective view from above the proximal body portion, the mounting assembly and the tool assembly of the DLU of the surgical instrument with the tool assembly in its non-articulated position;
FIG. 3E is a side perspective view from above the proximal body portion, the mounting assembly and the tool assembly shown inFIG 3D with the tool assembly in an articulated position;
FIG. 3F is a side perspective view from below the proximal body portion, the mounting assembly and the tool assembly of the DLU of the surgical instrument with the tool assembly in its non-articulated position;
FIG. 3G is a side perspective view from below the proximal body portion, the mounting assembly and the tool assembly shown inFIG 3F with the tool assembly in an articulated position;
FIG. 4 is a side cross-sectional view of the tool assembly of the DLU shown inFIG. 1A;
FIG. 5 is a top perspective view of the lock member actuator of the proximal body portion locking mechanism shown inFIG. 3;
FIG. 6 is a bottom perspective view of a locking member of the locking mechanism shown inFIG. 3;
FIG. 7 is a top view of the proximal end of the DLU proximal body portion shown inFIG. 1A with the locking mechanism in its locked position;
FIG. 8 is a cross-sectional view taken along section lines 8-8 ofFIG. 7;
FIG. 9 is a top view of the proximal end of the DLU proximal body portion shown inFIG. 1A with the locking mechanism in its unlocked position;
FIG. 10 is a cross-sectional view taken along section lines 10-10 ofFIG. 9;
FIG. 11 is a side perspective view of the DLU and surgical instrument shown inFIG. 1 prior to attachment of the DLU to the surgical instrument;
FIG. 12 is a top view of the proximal end of the DLU and the distal end of the surgical instrument shown inFIG. 11 prior to attachment to the distal end of the surgical instrument;
FIG. 13 is a top view of the proximal end of the DLU shown inFIG. 11 as the DLU is advanced linearly into the distal end of the surgical instrument;
FIG. 14 is a top view of the proximal end of the DLU and the distal end of the surgical instrument shown inFIG. 12 after the DLU has been advanced linearly but prior to locking the DLU to the surgical instrument;
FIG. 15 is a top view of the proximal end of the DLU and the distal end of the surgical instrument shown inFIG. 13 after the DLU has been advanced linearly and rotatably locked onto the surgical instrument;
FIG. 16 is a perspective view of a locking assembly for use with a surgical instrument in accordance with an embodiment of the present disclosure;
FIG. 17 is a perspective view of various components of the locking assembly ofFIG. 16;
FIG. 18 is an enlarged perspective view of a portion of the locking assembly ofFIGS. 16 and17 illustrated with the articulating tool assembly in a non-articulated position;
FIG. 19 is an enlarged perspective view of a portion of the locking assembly ofFIGS. 16-18 and including a link;
FIG. 20 is an enlarged perspective view of a portion of the locking assembly ofFIGS. 16-19 illustrated with the articulating tool assembly in an articulated position;
FIG. 21 is an enlarged perspective view of another locking assembly for use with a surgical instrument in accordance with an embodiment of the present disclosure;
FIG. 22 is an enlarged bottom perspective view of the locking assembly ofFIG. 21;
FIG. 23 is a perspective view of a drive beam having a plurality of layers and a closure apparatus in accordance with an embodiment of the present disclosure;
FIG. 24 is a perspective view of the drive beam and closure apparatus ofFIG. 23 with parts separated;
FIG. 25 is a cross-sectional view of a portion of the drive beam and closure apparatus ofFIGS. 23 and24;
FIG. 26 is a cross-sectional view of a drive beam and a closure apparatus in accordance with an embodiment of the present disclosure;
FIG. 27 is a cross-sectional view of the drive beam and closure apparatus ofFIG. 26;
FIG. 27a is a perspective view of a closure member manufactured in accordance with an embodiment of the present invention;
FIG. 27b is a cross-sectional view of the closure member shown inFIG 27a taken along section lines 27b-27b ofFIG. 27a;
FIG. 27c is a perspective view of the closure member shown inFIG. 27a prior to attachment of the insert;
FIG. 27d is a cross-sectional view of the closure member taken alongsection lines 27d-27d ofFIG. 27c;
FIG. 28 is a perspective view of a tool assembly in accordance with an embodiment of the present disclosure; and
FIG. 29 is an assembly view of the tool assembly ofFIG. 28.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed surgical instrument and DLU will now be described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views.
Referring toFIG. 1,surgical instrument 500 includes ahandle portion 510, abody portion 512, and a disposable loading unit ("DLU") 16.Handle portion 510 includes astationary handle 514 and a movable handle or trigger 516.Movable handle 516 is movable in relation tostationary handle 514 to advance acontrol rod 520 which projects from the distal end ofbody portion 512.Handle portion 510 andbody portion 512 may be constructed in the manner disclosed inU.S. Patent No. 6,330,965. Alternately, other surgical instruments can be used withDLU 16 to perform endoscopic surgical procedures.
Referring toFIGS. 1 and1A, briefly,DLU 16 includes atool assembly 17, aproximal body portion 200 and a mountingassembly 202.Body portion 200 has a proximal end adapted to releasably engage the distal end of a surgical instrument 500 (FIG. 11) in the manner to be discussed in detail below. Mountingassembly 202 is pivotally secured to a distal end ofbody portion 200 and is fixedly secured to a proximal end oftool assembly 17. Pivotal movement of mountingassembly 202 about an axis perpendicular to a longitudinal axis ofbody portion 200 affects articulation oftool assembly 17 between a non-articulated position in which the longitudinal axis oftool assembly 17 is aligned with the longitudinal axis ofbody portion 200 and an articulated position in which the longitudinal axis oftool assembly 17 is disposed at an angle to the longitudinal axis ofbody portion 200.
Referring toFIGS. 2-4,tool assembly 17 includes acartridge assembly 18 and ananvil assembly 20.Anvil assembly 20 includes ananvil portion 28 having a plurality of staple deforming concavities 30 (FIG. 4) and acover plate 32 secured to a top surface ofanvil portion 28.Cover plate 32 andanvil portion 28 define a cavity 34 (FIG. 4) therebetween which is dimensioned to receive a distal end of a drive assembly 212 (FIG. 3).Cover plate 32 encloses the distal end ofdrive assembly 212 to prevent pinching of tissue during actuation ofDLU 16. Alongitudinal slot 38 extends throughanvil portion 28 to facilitate passage of aretention flange 40 ofdrive assembly 212. Acamming surface 42 formed onanvil portion 28 is positioned to engage a pair ofcam members 40a supported onretention flange 40 ofdrive assembly 212 to effect approximation of the anvil and cartridge assemblies. A pair ofpivot members 44 are formed. A pair of stabilizingmembers 50 engage arespective shoulder 52 formed oncarrier 48 to preventanvil portion 28 from sliding axially in relation tostaple cartridge 54 ascamming surface 42 is pivoted aboutpivot members 44.
Cartridge assembly 18 includescarrier 48 which defines anelongated support channel 56 which is dimensioned and configured to receivestaple cartridge 54. Correspondingtabs 58 and slots 60 formed alongstaple cartridge 54 andelongated support channel 56, respectively, function to retainstaple cartridge 54 at a fixed location withinsupport channel 56. A pair of support struts 62 formed onstaple cartridge 54 are positioned to rest on side walls ofcarrier 48 to further stabilizestaple cartridge 54 withinsupport channel 56.Carrier 48 hasslots 46 for receivingpivot members 44 ofanvil portion 28 and allowinganvil portion 28 to move between spaced and approximated positions.
Staple cartridge 54 includes retention slots 64 (FIG. 2) for receiving a plurality of staples orfasteners 66 andpushers 68. A plurality of laterally spaced apartlongitudinal slots 70 extend throughstaple cartridge 54 to accommodateupstanding cam wedges 72 of an actuation sled 74 (FIG. 2). A centrallongitudinal slot 76 extends along substantially the length ofstaple cartridge 54 to facilitate passage of a knife blade 78 (FIG. 4). During operation ofsurgical stapler 10,drive assembly 212 abutsactuation sled 74 and pushesactuation sled 74 throughlongitudinal slots 70 ofstaple cartridge 54 to advancecam wedges 72 into sequential contact withpushers 68.Pushers 68 translate vertically alongcam wedges 72 withinfastener retention slots 64 andurge fasteners 66 fromretention slots 64 into staple deforming cavities 30 (FIG. 4) ofanvil assembly 20.
Referring toFIG. 3, mountingassembly 235 includes an upper mountingportion 236 and alower mounting portion 238. A centrally locatedpivot member 284 extends from upper mountingportion 236 through a respective opening 246a formed in afirst coupling member 246. Lower mountingportion 238 includes abore 239 for receiving pivot member 284 (seeFIG. 3F).Pivot member 284 extends throughbore 239 andopening 247a of asecond coupling member 247. Each ofcoupling members 246, 247 includes an interlocking proximal portion 246b, 247b configured to be received ingrooves 290 formed in the distal end of an inner housing which is formed from upper andlower housing halves 250 and 252. Couplingmembers 246, 247retain mounting assembly 235 and upper andlower housing halves 250 and 252 in a longitudinally fixed position in relation to each other while permitting pivotal movement of mountingassembly 235 in relation thereto.
Referring toFIGS. 3A-3C, eachcoupling member 246, 247 includes a cantileveredspring arm 246c which has adistal end 246d positioned to engage mountingassembly 235. More specifically, upper mountingportion 236 includes atop surface 236a which includes a recess 236b dimensioned to receivedistal end 246d ofspring arm 246c of arespective coupling member 246. Lower mountingportion 238 includes abottom surface 238a having a pair of raised surfaces 238b which define arecess 238c which is dimensioned to receivespring arm 247c of arespective coupling member 247. Alternatively, at least one recess may be formed in the proximal end oftool assembly 17.
As illustrated inFIGS. 3D-3G, when distal end ofspring arms 246c, 247c ofcoupling members 246, 247 are positioned inrecesses 236b and 238c of upper and lower mountingportions 236 and 238, respectively,spring arms 246c, 247c retain mountingassembly 235 in a non-articulated position.Spring arms 246c, 247c will retain mountingassembly 235 in its non-articulated position until a predetermined force sufficient to deflectspring arms 246c fromrecesses 236b and 238c is applied to effect articulation of mountingassembly 235 andtool assembly 17. When the predetermined force is applied to the mountingassembly 235 andtool assembly 17,spring arms 246c, 247c will spring or deflect outwardly fromrecesses 236b and 238c, as shown inFIGS. 3E and3G, to permit pivotal movement of mounting assembly 235 (and, thus, tool assembly 17) in relation to the distal end ofproximal body portion 200 of theDLU 16.
As discussed above,spring arms 246c and recesses 236b and 238c maintaintool assembly 17 in its non-articulated position until a predetermined force has been applied to mountingassembly 235 to disengagespring arms 246c, 247c fromrecesses 236b and 238c of mountingassembly 235. It is envisioned that the spring arms/recesses could be incorporated into any articulating surgical device including staplers, graspers (SeeFIG. 3H), powered sealing devices, e.g., RF sealing devices, etc. Further, although two spring arms/recesses are shown, a single spring arm can be provided. Moreover, the articulating tool assembly need not form part of a DLU but rather can be supported directly on the distal end of a surgical instrument. For example, the mounting assembly can be removably or irremovably secured to the tool assembly and secured directly to the distal end of a surgical instrument.
Upper housing half 250 andlower housing half 252 are contained within anouter sleeve 251 of body portion 200 (FIG. 3).Body portion 200 includes acutout 251a dimensioned to receive a boss orprojection 250a formed onupper housing half 250. The positioning ofprojection 250a within cutout 251a prevents axial and rotational movement of upper andlower housing halves 250 and 252 withinouter sleeve 251 ofbody portion 200. In one embodiment,boss 250a has a substantially rectangular configuration having a greater axial dimension than lateral dimension. The greater axial dimension provides increased surface area for preventing rotation of upper andlower housing halves 250 and 252 withinsleeve 251. Aproximal portion 250b ofboss 250a is ramped. Rampedproximal portion 250b allowssleeve 251 to be slid overboss 250a as upper andlower housing halves 250 and 252 are positioned withinsleeve 251. It is envisioned thatboss 250a may assume other configurations, e.g., circular, square, triangular, etc., and still achieve its intended function. Further,boss 250a can be repositioned anywhere alongupper housing half 250 or, in the alternative, be positioned onlower housing half 252 or partly on eachhousing half 250 and 252.
The proximal end orinsertion tip 193 ofupper housing half 250 includesengagement nubs 254 for releasably engaging the distal end of a surgical instrument in a bayonet-type fashion (seeFIGS. 1A and7). Housing halves 250 and 252 define achannel 400 for slidably receivingaxial drive assembly 212 therein. Anarticulation link 256 is dimensioned to be slidably positioned within aslot 402 formed between upper andlower housing halves 250 and 252. A pair of H-block assemblies 255 are positioned adjacent the distal end ofhousing portion 200 and adjacent the distal end ofaxial drive assembly 212 to prevent outward buckling and bulging ofdrive assembly 212 during articulation and firing ofsurgical stapling apparatus 10. Each H-block assembly 255 includes aflexible body 255a which includes a proximal end fixedly secured tobody portion 200 and a distal end fixedly secured to mounting assembly 235 (FIG. 3).
Aretention member 288 is supported onengagement section 270 ofaxial drive assembly 212.Retention member 288 includes a pair offingers 288a which are releasably positioned within slots or recesses 252a formed inlower housing half 252. In operation, whenSULU 16 is attached to a surgical instrument andaxial drive assembly 212 is actuated by applying a predetermined force to anactuation member 516 of the surgical instrument 500 (FIG. 11),axial drive assembly 212 is advanced distally to movedrive assembly 212 andretention member 288 distally. Asretention member 288 is advanced distally,fingers 288a are forced from recesses 252a to provide an audible and tactile indication that the surgical instrument has been actuated.Retention member 288 is designed to prevent inadvertent partial actuation ofDLU 16, such as during shipping, by maintainingaxial drive assembly 212 at a fixed position withinDLU 16 until a predetermined axial force has been applied toaxial drive assembly 212.
Axial drive assembly 212 includes anelongated drive beam 266 including adistal working head 268 and aproximal engagement section 270. In one embodiment,drive beam 266 is constructed from multiple stacked sheets of material.Engagement section 270 includes a pair ofresilient engagement fingers 270a and 270b which mountingly engage a pair of corresponding retention slots formed indrive member 272.Drive member 272 includes aproximal porthole 274 configured to receive distal end of a control rod 520 (FIG. 11) of a surgical instrument when the proximal end ofDLU 16 is engaged with thebody portion 512 of asurgical instrument 500.
Referring also toFIGS. 5-10,DLU 16 further includes a locking mechanism including a lockingmember 300 and a lockingmember actuator 302. Locking member 300 (FIG. 6) is rotatably supported within a longitudinal or axial slot 310 (FIG. 7) formed in a proximal portion ofupper housing half 250 ofbody portion 200 ofDLU 16. Lockingmember 300 is movable from a first position (FIGS. 7 and 8), in which lockingmember 300 maintainsdrive assembly 212 in a prefired position, to a second position (FIGS. 9 and 10), in which driveassembly 212 is free to move axially.
As illustrated inFIG. 6, lockingmember 300 includessemi-cylindrical body 312 which is slidably positioned withintransverse slot 310 formed inupper housing half 250 ofbody portion 200.Body 312 includes a radially inwardly extendingcam member 314 and a radially inwardly extendingfinger 316.Finger 316 is dimensioned to be slidably received within a notch or slot 270c (FIG. 3) formed indrive assembly 212. Engagement offinger 316 in notch 270c ofdrive assembly 212 prevents drive assembly 212 from moving linearly withinbody portion 200 and, thus, prevents actuation ofDLU 16.
Referring toFIGS. 3,5 and7, a lockingmember actuator 302 is slidably positioned within a axial slot 320 (FIG. 7) formed inupper housing half 250 ofbody portion 200 ofDLU 16.Actuator 302 includes aproximal abutment member 322, adistal spring guide 324, and acentral cam slot 326.Axial slot 320 intersectstransverse slot 310 such thatcam member 314 of lockingmember 300 is slidably positioned withincam slot 326 of lockingmember actuator 302. A biasing member or spring 328 (FIG. 7) is positioned aboutspring guide 324 between adistal surface 330 ofactuator 302 and a wall 332 (FIG. 7) defining the distal end ofaxial slot 320.Spring 328 urges actuator 302 to its retracted position withinaxial slot 320. In its retracted position,abutment member 322 is positioned on and extends radially outwardly of the proximal end ofDLU 16adjacent insertion tip 193 ofproximal body portion 200 andcam slot 326 is positioned to locatecam member 314 such thatfinger 316 oflock member 300 is positioned within notch 270c ofdrive assembly 212.
FIGS. 11-15 illustrateDLU 16 andsurgical instrument 500 prior to and during attachment ofDLU 16 tosurgical instrument 500. Prior to attachment ofDLU 16 ontosurgical instrument 500,spring 328 urges actuator 302 to its retracted position to movelock member 300 to its locked position as discussed above. Wheninsertion tip 193DLU 16 is linearly inserted into the open end 522 (FIG. 11) of the body portion 512 (FIG. 13) of asurgical instrument 500,nubs 254 move linearly through slots (not shown) formed in open end 522 ofbody portion 512. Asnubs 254 pass through the slots, theproximal end 322a ofabutment member 322, which is angularly offset fromnubs 254, abuts awall 276c defining the slots for receivingnubs 254. AsDLU 16 is moved further intobody portion 512, lockingmember actuator 302 is moved from its retracted position to its advanced position in the direction indicated by arrow "T" inFIG. 14. Asactuator 302 is moved to its advanced position,lock member 300 is cammed in the direction indicated by arrow "U" inFIG. 14 from its locked position (FIG. 8) engaged withdrive assembly 212 to its unlocked position (FIG. 10) to movefinger 316 from notch 270c. The locking mechanism including lockingmember 300 and lockingmember actuator 302 prevents accidental or inadvertent advancement or manipulation of the drive member ofDLU 16 such as during loading ofDLU 16 onto asurgical instrument 500.
WhenDLU 16 has been moved linearly in relation toinstrument 500 to a position wherein aproximal surface 530 ofbody portion 200 abutsinner surface 276c of body portion 512 (FIG. 15),DLU 16 can be rotated in relation tobody portion 512 in a bayonet-type action to positionnubs 254 withinopenings 536 ofbody portion 512 to lockDLU 16 ontobody portion 512. It is envisioned that other coupling types besides bayonet couplings may be used to connectDLU 16 toinstrument 500, e.g., spring detent or snap-fit couplings, friction fit couplings, interlocking members, threaded couplings etc.
In an embodiment of the present disclosure illustrated inFIGS. 16-20, a lockingassembly 600 is illustrated for use withsurgical instrument 500 and disposable loading unit 16 (seeFIG. 1, for example). In the illustrated embodiments, lockingassembly 600 includes ahousing 602, apusher 604, arod 606, aslide 608, at least onespring 610, acam finger 612, apivot plate 614 havingslots 616 and alink 618. Lockingassembly 600 generally helps tool assembly 17 (seeFIG. 1, for example) maintain its position during firing ofsurgical instrument 500.
Referring toFIGS. 16 and17, a portion of lockingassembly 600 is at least partially contained within ahousing 602.Figure 16 illustrates lockingassembly 600 disposed in relation tohousing 602, whileFigure 17 illustrates lockingassembly 600 isolated fromhousing 602. In the illustrated embodiment ofFIG. 17,pusher 604 is shown withrod 606 extending distally therefrom.Slide 608 extends distally fromrod 606 and is in a slidable relationship therewith, thus allowingslide 608 to move axially with respect torod 606.Spring 610 or pair of springs (not explicitly shown in this embodiment) distally biases slide 608 fromrod 606.
Now referring toFIGS. 18-20,cam finger 612 andpivot plate 614 are illustrated.Cam finger 612 extends distally fromslide 608 andpivot plate 614 may be disposed on mounting assembly 235 (seeFIG. 3), for example. It is envisioned thatpivot plate 614 may be disposed on or incorporated with a portion oftool assembly 17. A plurality of slots 616 (fiveslots 616 are illustrated) is disposed onpivot plate 614 and are sized to accept at least a portion ofcam finger 612 therein. Upon different amounts of articulation of tool assembly 17 (including no substantial articulation) with respect to body portion 512 (seeFIG. 1, for example),cam finger 612 is approximately aligned with anindividual slot 616 ofpivot plate 614.FIGS. 18 and19 illustratecam finger 612 substantially aligned with acenter slot 616a (hidden from view inFIG. 19) andFIG. 20 illustratescam finger 612 substantially aligned with a side slot 616b.
Link 618, illustrated inFIGS. 17 and19, is in mechanical engagement withpivot plate 614 andcam finger 612. (InFIG. 18, the link has been removed.)Link 618 is illustrated having anopening 620 and a slot 622 (FIG. 19).Opening 620 is in a pivotal relationship with aboss 624 onpivot plate 614 andslot 622 is slidably engaged withcam finger 612. This relationship allows for articulation ofpivot plate 614 with respect tobody portion 512 and for longitudinal translation ofslide 608 with respect to pivotplate 614.
In operation, upon at least a partial actuation of movable handle 516 (seeFIG. 1, for example),pusher 604 is forced distally, e.g., via control rod 520 (seeFIG. 11, for example), thus causing distal translation ofcam finger 612 at least partially into aslot 616 ofpivot plate 614. It is envisioned that actuatingmovable handle 516 toapproximate cartridge assembly 18 and an anvil assembly 20 (seeFIG. 1A, for example) also functions to translatecam finger 612 distally. In such an embodiment, when articulatingtool assembly 17 is in place and clamped on tissue, further articulation cannot be accomplished (without releasingmovable handle 516, for example). Thus, lockingassembly 600 helps maintain articulatingtool assembly 17 in position with respect tobody portion 512, prior to emplacing staples into tissue, for example.
As discussed above,spring 610 distally biases slide 608 fromrod 606. This biasing provided byspring 610 helps ensurecam finger 612 is not accidentally or prematurely dislodged fromslot 616 ofpivot plate 614, which may result in a significant amount of "play" therebetween. Additionally, the distal bias provided byspring 610 helps eliminate manufacturing tolerances and/or clearances that are present betweenslide 608 andpivot plate 614. It is also envisioned that at least a portion ofcam finger 612 and/or slot 616 may be wedge-shaped to help reduce any unintended movement therebetween. In such an embodiment, a distal portion ofcam finger 612 andslot 616 would be narrower than a corresponding proximal portion.
In an embodiment of the present disclosure illustrated inFIGS. 21 and22, a lockingassembly 700 is illustrated for use withsurgical instrument 500 and disposable loading unit 16 (seeFIG. 1, for example). In the illustrated embodiment, lockingassembly 700 includes anadapter 702, apusher 704, apivot 706, a biasing element (e.g., a pair of springs 708) and alink 710. Lockingassembly 700 generally helps maintaintool assembly 17 in a predetermined position.
With reference toFIG. 21,adapter 702 of lockingassembly 700 is generally housed within body portion 512 (seeFIG. 1, for example) ofsurgical instrument 500 or withindisposable loading unit 16. In the illustrated embodiment,pusher 704 is located distally of a pair ofsprings 708.Pusher 704 is distally biased via the pair ofsprings 708 towardspivot 706 of articulatingtool assembly 17. A distal portion ofpusher 704 includes a pusher mating surface 712 (FIG. 22) which is shaped and dimensioned to mate with a pivot mating surface 714 (FIG. 22) disposed adjacent a proximal portion ofpivot 706.Link 710 is illustrated in mechanical cooperation with a portion ofpusher 704 and pivotably connected to a portion ofpivot 706, thus allowing articulatingtool assembly 17 to move between its first position and its second position with respect tobody portion 512. More specifically, link 710 includes anopening 711 that fits over aprotrusion 707 ofpivot 706, thus allowing pivotal movement therebetween. Further, link 710 is slidably engaged with a portion ofadapter 702, thus allowing longitudinal movement therebetween.
Now referring toFIG. 22,pusher mating surface 712 is substantially flat along a majority of its length in this embodiment. Correspondingly, pivotmating surface 714 is also flat along a majority of its length in the illustrated embodiment. Thus, the distal bias ofpusher 704 towards pivot 706 (in the direction of arrow A) via the pair ofsprings 708, helps maintain articulatingtool assembly 17 in its first, non-articulated, position, as the biasing force helps articulatingtool assembly 17 resist pivoting. While twosprings 708 are illustrated, more orfewer springs 708 may be provided.
To pivot articulatingtool 17 from its first, non-articulated position, the distal biasing force from pair ofsprings 708 must be overcome. Such a pivoting action, movespusher 704 proximally (in the direction of arrow B) against the bias of pair ofsprings 708. It is also envisioned thatpusher mating surface 714 includes detents (not explicitly shown in this embodiment) to help stabilize articulatingjaw member 17 in selected articulated positions.
With continued reference toFIG. 22,pivot 706 includes ashelf 716 thereon. As shown inFIG. 22,shelf 716 overlaps at least a portion ofpusher 704 whenpusher mating surface 712 is in contact withpivot mating surface 714.Shelf 716 is situated and configured to help prevent tissue from being pinched betweenpusher 704 and pivot 706 when articulatingtool assembly 17 is rotated and/or articulated.
In an embodiment of the present disclosure illustrated inFIGS. 23-25, amulti-layered drive beam 750 having a plurality oflayers 750a - 750e is illustrated and may be included in a disposable loading unit 16 (seeFIG. 1, for example). Aclosure apparatus 760, such as an I-beam, is also illustrated.Closure apparatus 760 includes ahorizontal portion 762 that is advanceable into camming surface 42 (or other contact surface) to approximate toolassembly tool assembly 17, as described in detail above with reference toFIG. 2.
With reference toFIG. 24,multi-layered drive beam 750 having fivelayers 750a - 750e is illustrated. It is envisioned and within the scope of the present disclosure that fewer or more layers may be used to formmulti-layered drive beam 750. It is also envisioned thatmulti-layered drive beam 750 may replacedrive beam 266 in other embodiments of this disclosure. Use ofmulti-layered drive beam 750 may provide increased strength and flexibility during use, specifically, for instance, whiletool assembly 17 is in an articulated position.
A plurality ofcutouts 770 is illustrated inFIGS. 23-25 which extend through each layer ofmulti-layered drive beam 750. Although the figures show between five and ten cutouts per layer ofmulti-layered drive beam 750, the exact number ofcutouts 770 may be fewer than five, between five and ten, or greater than ten. Additionally,cutouts 770 of adjacent layers ofdrive beam 750 may or not align with each other. The use ofcutouts 770 reduces cross-sectional dimensions ofdrive beam 750 and allows for bending force adjustment. Whilerectangular cutouts 770 are illustrated, the use ofcutouts 770 having other regular or non-regular shapes is also contemplated.
The attachment of eachlayer 750a - 750e ofmulti-layered drive beam 750 and the attachment toclosure apparatus 760 are illustrated inFIG. 25. In the illustrated embodiment, an outer layer (750a or 750e ofFIG. 24) is affixed toclosure apparatus 760 in two locations (each location being indicated by numeral 780 inFIG. 25), via a pair of spot welds, for example. It is also envisioned that eachouter layer 750a, 750e includes anaperture 776 that fits over aboss 778 protruding fromclosure apparatus 760. Eachouter layer 750a, 750e is also affixed to an adjacent layer (e.g., 750b or 750d) in two locations (each location being indicated by numeral 781 inFIG. 25), possibly via a pair of spot welds. Further, each inner layer (e.g., 750b, 750c and 750d) is attached to an adjacent inner layer (for instance, 750b is attached to 750c; 750c is attached to 750b and 750d; and 750d is attached to 750c) in two locations, via spot welds, for example. While spot welding is disclosed as an attachment method, other methods for attaching each layer to each other and the outer layers to the closure apparatus are envisioned and within the scope of the present disclosure. The illustrated embodiments show attachments points 780 of inner layersadjacent closure apparatus 760, but it is envisioned and within the scope of the present disclosure that attachment points 780 are disposed in other locations ondrive beam 750. Additionally, it is envisioned that at least one layer ofdrive beam 750 is made of a metal, such as stainless steel. Portions ofdrive beam 750 and/orclosure apparatus 760 may also be made of or at least partially coated with a plastic material, as described below. Further, closure apparatus 790 may include a cutting surface 766 (FIG. 23) thereon for cutting tissue.
In an embodiment of the present disclosure illustrated inFIGS. 26 and27, aclosure apparatus 800 and a portion ofdrive beam 802 are shown. Closure apparatus and/or a contact surface (e.g., camming surface 42) of tool assembly 17 (seeFIG. 2, for example) may include a plastic surface or plastic coating. In this embodiment,closure apparatus 800 is illustrated having a pair ofcaps 804 at least partially coveringhorizontal portions 806 ofclosure apparatus 800.Caps 804 may be made of plastic in this embodiment. Such plastic surfaces disposed onclosure apparatus 800 and/or contact surface oftool assembly 17 generally reduce the amount of friction therebetween vis-à-vis two metal surfaces. That is, a plastic to metal or a plastic to plastic interaction may create less friction than interaction between a pair of metal surfaces. This reduced amount of friction may correspond to a reduced firing force.
It is envisioned that a portion ofclosure apparatus 800, such as pair ofcaps 804, is made of plastic, overmolded with plastic or includes a plastic coating. Additionally, a contact surface oftool assembly 17, or at least a portion thereof, may also be made of plastic, be overmolded with plastic or include a plastic coating.
In an embodiment of the disclosure,closure apparatus 800 may include an I-shaped cross section, as illustrated inFIGS. 26 and27. Additionally,closure apparatus 800 and drivebeam 802 may be part of adisposable loading unit 16 and/or part of asurgical instrument 500 that is able to articulate. Further,drive beam 802 may include a single layer or a plurality of layers (as shown inFIG. 26) and at least a portion ofdrive beam 802 may be made of plastic. Still further,closure apparatus 800 may include a cutting surface 808 (FIG. 27) thereon for cutting tissue.
With continued reference toFIGS. 26 and27,plastic cap 804 may include a reinforcedsection 810 which may increase the strength ofclosure apparatus 800 or may provide a stronger connection betweencap 804 andhorizontal portion 806 ofclosure apparatus 800. It is also envisioned thatcap 804 may be removably attached toclosure apparatus 800. In such an embodiment,cap 804 may be removed and replaced if any substantial wearing or damage occurs.
FIGS. 27a-27d illustrate an alternative embodiment of the presently disclosed closure member shown generally as 800'. As discussed above with respect toclosure member 800, closure member 800' may include an I-shaped cross-section which includes an upper flange portion 802', a lower flange portion 804' and a vertical beam portion 806' which extends between upper flange portion 802' and lower flange portion 804'. Closure member 800' can be formed of metal, e.g., stainless steel, etc. Each of upper flange portion 802' and lower flange portion 804' includes an external surface 807' and an internal surface 808'. Each internal surface 808' includes a cutout or recess 810' (FIG. 27d) which is dimensioned to receive an insert 812' formed of a material having a low coefficient of friction. In one embodiment, insert 812' is formed of plastic although it is envisioned that other materials having a low coefficient of friction and the requisite strength characteristics may also be used to form insert 812'. As illustrated, insert 812' may extend slightly below the internal surface 808' of upper flange portion 802' and slightly above the internal surface 808' of lower flange portion 804'. Although inserts 812' are illustrated as extending along only a portion of the length of internal surfaces 808' of upper and lower flange portions 802' and 804', it is envisioned that inserts 812' may extend over the entire or substantially the entire length of internal surfaces 808'.
Vertical beam portion 806' includes a cutout 814' dimensioned to receive a drive beam (See, e.g.,drive beam 802 inFIG. 27) and a knife blade 816'. Knife blade 816' can be secured to vertical beam portion 806', such as by welding, or machined directly therein. Similarly, the drive beam can be welded to closure member 800', formed integrally therewith, or secured to closure member 800' using other known fastening techniques.
Referring toFIGS. 27a and27c, the distal edge 819' of lower flange portion 804' includes a chamfer or radiused edge 820'. The distal edge 819' is the edge that first engagestool assembly 17. In one embodiment, radiused edge 820' is spaced from insert 812' and is positioned to effect approximation of the pivotable jaw of the stapling device. SeeFIG. 1.
Referring toFIGS. 27c and 27d, in one embodiment insert 812' (FIG. 27a) is attached to upper flange portion 802' and lower flange portion 804' by forming the insert 812' in place. This may be done using an injection molding process. In one embodiment of the process, a hole 822' is drilled into and through upper and/or lower flange portions 802' and 804' such as to communicate with recesses 810' of upper flange portion 802' and lower flange portion 804'. Each hole 822' communicates from the external surface 806' with both recesses 810' on internal surface 808' of upper or lower flange portions. Alternatively, two holes can be drilled through each of upper and lower flange portions 802' and 804', with each hole communicating with one recess on one side of vertical beam portion 806'. Next, closure member 800' is positioned within a mold and mold material is injected through the hole 822' into recesses 810' to form inserts 812'. The mold can be configured to provide any desired insert configuration. After the molding step, the insert or inserts 812' can be machined or further shaped and the closure member 800' can be machined or cleaned in a known manner to prepare closure member 800' for use in a surgical device.
In an embodiment of the present disclosure illustrated inFIGS. 28 and29, atool assembly 850 is illustrated.Tool assembly 850 of this embodiment includes achannel 852, afirst attachment member 860, asecond attachment member 870, ananvil assembly 880, afirst attachment rod 890 and asecond attachment rod 892. First andsecond attachment rods 890, 892 provide a strong connection facilitating the elements oftool assembly 850 to remain together.
Channel 852 includes an opening 854 (two openings are illustrated) adjacent its proximal end andfirst attachment member 860 includes a boss 862 (two bosses are illustrated) extending therefrom.Channel 852 is connectable to first attachment member by placing opening(s) 854 over boss(es) 862, thus providing a pivotal connection therebetween. Although not explicitly illustrated in the present embodiment,channel 852 may house a plurality of surgical fasteners or a staple cartridge.
Anvil assembly 880 includes ananvil cover 882 and ananvil 886.Anvil 886 is configured for mechanical engagement withanvil cover 882, e.g., via a snap-fit connection. Anaperture 884 extends at least partially through a portion ofanvil cover 882.Aperture 884 is configured to fit over aprotrusion 872 disposed onsecond attachment member 870, thereby providing a connection betweenanvil assembly 880 andsecond attachment member 870. Additionally,anvil cover 882 includes at least oneopening 888 extending at least partially therethrough in an embodiment of the disclosure.Opening 888 is configured to fit overboss 862 offirst attachment member 860. In such an embodiment,anvil assembly 880 may be pivoted with respect tofirst attachment member 860 andsecond attachment member 870.
First attachment member 860 includes afirst opening 864 and a second opening 866 extending therethrough.Second attachment member 870 also includes afirst opening 874 and asecond opening 876 extending therethrough (FIG. 29). Further,first attachment member 860 andsecond attachment member 870 are in mechanical engagement, such thatfirst openings 864, 874 substantially align andsecond openings 866, 876 substantially align.
To securefirst attachment member 860 with second attachment member 870 (and thus channel 852 and anvil assembly 880),first attachment rod 890, or a portion thereof, is inserted throughfirst openings 864 and 874. To further secure the elements oftool assembly 850,second attachment rod 892, or a portion thereof, is inserted throughsecond openings 866 and 876. It is envisioned thatfirst attachment rod 890 and/orsecond attachment rod 892 are rivets, such as two-part rivets that are tightenable.
In an embodiment of the disclosure,tool assembly 850 is part of a disposable loading unit, which may be able to articulate. Articulation oftool assembly 850 may be facilitated by pivotably attachingtool assembly 850 to a body portion of a surgical instrument viaprotrusion 874 extending fromsecond attachment member 870 and a link (such aslink 710 inFIG. 21). Additionally, a method of assemblingtool assembly 850, as described above, is contemplated by the present disclosure.
It will be understood that various modifications may be made to the embodiments disclosed herein. For example, the above-described lock assembly may be incorporated into a variety of surgical instruments which include DLUs and is not limited to use on linear staplers. Further, the DLU may be configured to receive an insertion tip of surgical instrument in contrast to that disclosed. Therefore, the above description should not be construed as limiting, but merely as exemplifications of various embodiments.

Claims

A method of manufacturing a closure member for a surgical instrument, the method comprising the following steps:
providing a closure member (800') being configured to engage the contact surface of a tool assembly of said surgical instrument, said closure member including an upper flange portion (802'), a lower flange portion (804') and a vertical beam portion (806') interconnecting the upper flange portion and the lower flange portion, the upper and lower flange portions having an internal surface (808') and an external surface (807');
drilling a hole (822') through at least one of the upper and lower flange portions, the hole extending from the external surface to the internal surface of the at least one upper and lower flange portion; and
injecting a material (812') having a low coefficient of friction through the hole using an injection molding process to cover at least a portion of the internal surface of the at least one upper and lower flange portion.
The method according to Claim 1, wherein the at least one upper and lower flange portion includes both the upper and lower flange portions.
The method according to Claim 1, wherein the step of injecting a material includes covering substantially the entire internal surface of the at least one upper and lower flange portion.
The method according to Claim 1, wherein the material having the low coefficient of friction is a plastic material.
The method according to Claim 1, wherein the step of providing a closure member includes providing a closure member comprising a recess (810') in the internal surface of the at least one upper and lower flange portion.
The method according to Claim 5, wherein the step of injecting includes injecting said material into the recess.
The method according to Claim 6, wherein the step of injecting a material into the recess includes injecting said material into the recess such that the material extends inwardly of the internal surface.
The method according to Claim 7, further including the step of machining the material after the step of injecting.